import { useRef, useState } from "react";
import {
  Home,
  LayoutGrid,
  List,
  LogOut,
  Moon,
  Palette,
  Search,
  Settings,
  Shield,
  Sun,
  Tv,
} from "lucide-react";
import { SCHEMES, type Scheme, type ThemePrefs } from "../lib/theme";
import type { FeedFilters, Me } from "../lib/api";
import type { Page } from "../lib/urlState";
import SyncStatus from "./SyncStatus";
import NotificationCenter from "./NotificationCenter";

function IconBtn(props: React.ButtonHTMLAttributes<HTMLButtonElement>) {
  const { className = "", ...rest } = props;
  return (
    <button
      {...rest}
      className={`p-2 rounded-lg text-muted hover:text-fg hover:bg-card transition ${className}`}
    />
  );
}

function ThemeMenu({
  theme,
  setTheme,
}: {
  theme: ThemePrefs;
  setTheme: (t: ThemePrefs) => void;
}) {
  return (
    <div className="glass absolute right-0 mt-2 w-60 rounded-xl p-3 z-30 animate-[popIn_0.16s_ease]">
      <div className="text-xs uppercase tracking-wide text-muted mb-2">Color scheme</div>
      <div className="grid grid-cols-4 gap-2 mb-3">
        {SCHEMES.map((s) => (
          <button
            key={s.id}
            onClick={() => setTheme({ ...theme, scheme: s.id as Scheme })}
            title={s.name}
            className={`h-9 rounded-lg border-2 transition ${
              theme.scheme === s.id ? "border-fg" : "border-transparent"
            }`}
            style={{ background: s.swatch }}
          />
        ))}
      </div>
      <div className="text-xs uppercase tracking-wide text-muted mb-2">Text size</div>
      <input
        type="range"
        min={0.9}
        max={1.3}
        step={0.02}
        value={theme.fontScale}
        onChange={(e) => setTheme({ ...theme, fontScale: Number(e.target.value) })}
        className="w-full accent-accent"
      />
      <div className="text-right text-xs text-muted">
        {Math.round(theme.fontScale * 100)}%
      </div>
    </div>
  );
}

export default function Header({
  me,
  theme,
  setTheme,
  filters,
  setFilters,
  view,
  setView,
  page,
  setPage,
  onOpenSettings,
}: {
  me: Me;
  theme: ThemePrefs;
  setTheme: (t: ThemePrefs) => void;
  filters: FeedFilters;
  setFilters: (f: FeedFilters) => void;
  view: "grid" | "list";
  setView: (v: "grid" | "list") => void;
  page: Page;
  setPage: (p: Page) => void;
  onOpenSettings: () => void;
}) {
  const [menuOpen, setMenuOpen] = useState(false);

  async function logout() {
    await fetch("/auth/logout", { method: "POST", credentials: "include" });
    location.reload();
  }

  return (
    <header className="h-14 shrink-0 border-b border-border bg-surface/80 backdrop-blur flex items-center gap-3 px-4 z-20">
      <button
        onClick={() => setPage("feed")}
        className="text-xl font-bold tracking-tight select-none"
        title="Feed"
      >
        Sub<span className="text-accent">feed</span>
      </button>

      <SyncStatus />

      {page === "feed" ? (
        <div className="flex-1 max-w-xl mx-auto relative">
          <Search className="w-4 h-4 absolute left-3 top-1/2 -translate-y-1/2 text-muted" />
          <input
            value={filters.q}
            onChange={(e) => setFilters({ ...filters, q: e.target.value })}
            placeholder="Search your subscriptions…"
            className="w-full bg-card border border-border rounded-full pl-9 pr-4 py-2 text-sm outline-none focus:border-accent"
          />
        </div>
      ) : (
        <div className="flex-1 text-center text-sm font-semibold">Channel manager</div>
      )}

      <div className="flex items-center gap-1">
        {page === "feed" && (
          <IconBtn
            onClick={() => setView(view === "grid" ? "list" : "grid")}
            title={view === "grid" ? "List view" : "Grid view"}
          >
            {view === "grid" ? <List className="w-5 h-5" /> : <LayoutGrid className="w-5 h-5" />}
          </IconBtn>
        )}
        <IconBtn
          onClick={() => setTheme({ ...theme, mode: theme.mode === "dark" ? "light" : "dark" })}
          title="Toggle dark / light"
        >
          {theme.mode === "dark" ? <Sun className="w-5 h-5" /> : <Moon className="w-5 h-5" />}
        </IconBtn>
        <div className="relative">
          <IconBtn onClick={() => setMenuOpen((o) => !o)} title="Theme">
            <Palette className="w-5 h-5" />
          </IconBtn>
          {menuOpen && (
            <>
              <div className="fixed inset-0 z-20" onClick={() => setMenuOpen(false)} />
              <ThemeMenu theme={theme} setTheme={setTheme} />
            </>
          )}
        </div>

        <NotificationCenter filters={filters} setFilters={setFilters} />

        <div className="pl-1">
          <AccountMenu
            me={me}
            logout={logout}
            page={page}
            setPage={setPage}
            onOpenSettings={onOpenSettings}
          />
        </div>
      </div>
    </header>
  );
}

function Avatar({ me, className = "" }: { me: Me; className?: string }) {
  return me.avatar_url ? (
    <img src={me.avatar_url} alt="" className={`rounded-full ${className}`} />
  ) : (
    <div className={`rounded-full bg-card grid place-items-center font-semibold ${className}`}>
      {(me.display_name?.[0] ?? me.email[0] ?? "?").toUpperCase()}
    </div>
  );
}

function AccountMenu({
  me,
  logout,
  page,
  setPage,
  onOpenSettings,
}: {
  me: Me;
  logout: () => void;
  page: Page;
  setPage: (p: Page) => void;
  onOpenSettings: () => void;
}) {
  const [open, setOpen] = useState(false);
  const closeTimer = useRef<ReturnType<typeof setTimeout> | null>(null);

  function openNow() {
    if (closeTimer.current) clearTimeout(closeTimer.current);
    setOpen(true);
  }
  function closeSoon() {
    closeTimer.current = setTimeout(() => setOpen(false), 220);
  }

  const itemClass =
    "w-full flex items-center gap-2 text-sm px-2 py-2 rounded-lg text-muted hover:text-fg hover:bg-card transition";

  return (
    <div
      className="relative"
      onMouseEnter={openNow}
      onMouseLeave={closeSoon}
    >
      <button
        onClick={() => setOpen((o) => !o)}
        title={me.email}
        className="block rounded-full ring-2 ring-transparent hover:ring-border focus:outline-none focus:ring-accent transition"
      >
        <Avatar me={me} className="w-8 h-8 text-xs" />
      </button>

      {open && (
        <div className="glass absolute right-0 mt-2 w-64 rounded-xl p-3 z-30 animate-[popIn_0.16s_ease]">
          <div className="flex items-center gap-3 pb-3 border-b border-border">
            <Avatar me={me} className="w-10 h-10 text-sm shrink-0" />
            <div className="min-w-0">
              <div className="text-sm font-semibold truncate">
                {me.display_name ?? me.email.split("@")[0]}
              </div>
              <div className="text-xs text-muted truncate">{me.email}</div>
            </div>
          </div>

          {me.role === "admin" && (
            <div className="flex items-center gap-1.5 mt-2 text-[11px] font-medium text-accent">
              <Shield className="w-3.5 h-3.5" />
              Admin
            </div>
          )}

          <div className="mt-2 flex flex-col">
            {page === "channels" ? (
              <button onClick={() => { setPage("feed"); setOpen(false); }} className={itemClass}>
                <Home className="w-4 h-4" />
                Feed
              </button>
            ) : (
              <button onClick={() => { setPage("channels"); setOpen(false); }} className={itemClass}>
                <Tv className="w-4 h-4" />
                Channels
              </button>
            )}
            <button onClick={() => { onOpenSettings(); setOpen(false); }} className={itemClass}>
              <Settings className="w-4 h-4" />
              Settings
            </button>
            <button onClick={logout} className={itemClass}>
              <LogOut className="w-4 h-4" />
              Sign out
            </button>
          </div>
        </div>
      )}
    </div>
  );
}